Washing method and composition

ABSTRACT

It is disclosed a process for cleaning vehicles, especially cars, with an alkaline washing composition, preferably comprising one or more surfactants, where the washing composition is sprayed onto the vehicle with one or more nozzles or foam generators and where the alkaline washing composition in connection with the spraying onto the vehicle is combined with an aqueous solution of a cellulose derivative forming a semi-stable composition with congeals and absorbs/adsorbs the dirt particles removing them from the surface when the composition is rinsed off. It is preferred to add fibers in the rinsing water when hosing the composition off or in the cleaning solutions, and it is also preferred to perform the process at a pressure, e.g. 1-150 bars. The two components forming the cleaning composition are preferably combined by using an ejector system operated with water for obtaining the relevant concentrations of each component. The fiber dispersion may also be used separately with conventional washing compositions.

BACKGROUND

The present invention presents an improved system and composition forwashing dirty surfaces, and which is especially developed for washingvehicles.

It is previously known numerous types of washing compositions to be usedwhen washing e.g. vehicles, but all of these compositions are meant tobe used together with either manual washing or with rotating brushes orhanging cloth which mechanically remove dust and dirt from the surface.Such manual or mechanical washing is, however, abrasive on the surfaceand may in many cases destroy the finish or the paint on the vehicle.Previously it has also been attempted to hose off the layer of dust fromthe surfaces of the vehicle, but it has been found that the layer ofdust adheres so strongly that spraying or hosing even at high pressurehas not been satisfactory even with the addition of known washingsolutions.

The need to clean vehicles without any mechanical treatment hasincreased, and has been the basis for attempts to find solutions to thisproblem the last 10 years by using different kinds of compositions andsystems. The common factor for all these compositions is that thesurface does not become fully clean on account of a fine layer whichwill often remain and which is not being removed by high pressurespraying in combination with a cleaning composition without using strongcompositions which will have negative effects on the surf ace of thevehicle, and will also represent a negative effect on the environmentand corrode the car.

Many manufacturers have attempted to use acids and/or alkaline solutionsand also combinations thereof, but the side effects with corrosion bothon the car itself and also on sewer systems etc.

SUMMARY

According to the present invention it has surprisingly been found that acomposition comprising a mixture of a water-soluble cellulosederivative, such as a hydroxyl cellulose derivative, e.g. ethyl hydroxycellulose, in a neutral to alkaline aqueous dispersion mixed with analkaline detergent, will form, an agglomerate when it is added to thesurface which is to be rinsed, and which partially adsorbs and partiallyabsorbs the dirt particles so that they no longer adhere to the surfaceand easily may be hosed off together with the agglomerate. This saves toa large degree the surface and represents a significant improvement ofthe cleaning result compared with the previously known washingcompositions.

The new effect of the present washing solution and system is that it ismade more viscous in the foaming process and that it is preferablysupplied with non-abrasive fiber particles in the rinsing/hosing processsubstituting the mechanical work being necessary in the previouscar-washing systems as mentioned supra.

The surprising effect of the cleaning solution and process according tothe present invention is that each of the cellulose derivative solutionand the alkaline solution are readily water-soluble, but correspondingconcentrations of stem solutions mixed directly with each other are notsoluble. Thus a one-component system with these two stem solutions isnot possible, and the two stem solutions enter a temporary semi-stablecondition when mixed with water in a container/feeding tank immediatelyprior to its introduction into the foam generator, from which thecombined foam may be sprayed onto the surface which is to be cleaned,and whereupon the composition is congealing absorbing and adsorbing allthe dirt particles onto which it is applied. On account of the limitedstability of the washing composition according to the invention, only aquantity large enough to clean one or a small number of vehicles or carsis made continuously as needed, and the foaming process increases thevolume of the solution to such a degree that the pre-made quantity isenough to clean the vehicle. In this connection a quantity of 2-10 1premade non-foamed cleaning solution according to the invention willcover an ordinary vehicle/car when expanded as a foam, and the volume ofsuch a foam may be increased 3-8 times. Alter a dwell time of 30-60 sec.the dirt is then absorbed/adsorbed into the solution.

When hosing off the cleaning solution and dirt from the surface of thevehicle, it is preferred that fibers are introduced in the rinsing water(see infra), and it is also preferred that this is done at a pressureranging from 1 to 150 bar.

The aqueous dispersion of the hydroxy cellulose derivative added aneutral to alkaline solution of a conventional washing composition givesbetter washing properties. When using conventional washing compositionstogether with the cellulose derivative according to the presentinvention, it has been found that there is achieved a synergistic effectwhen mixing the cellulose derivative and the alkaline washingcomposition according to the invention, which increases the cleaningeffect of the end product significantly compared to each of thecomponents used alone. Furthermore it has been found that combining thecellulose derivative with the conventional alkaline solution atconcentrations which should make them mutually un-mixable, andintroducing such a composition through a foam generator, preferably athigh pressure, to the surface which is to be cleaned, there is produceda semi-stable composition which after a time congeals to a gel-likesubstance which removes the dust and dirt and leaves the surf ace cleanwithout any form of abrasive treatment.

BRIEF DESCRIPTION OF THE DRAWINGS

Below the invention will be more closely disclosed with reference toembodiment examples and also with reference to the figures where:

FIG. 1 shows one embodiment of the system and process according to theinvention, and

FIG. 2 shows another and further developed embodiment of the system andprocess according to the invention.

DETAILED DESCRIPTION

In those cases where there is referred to percentages in the disclosure,unless otherwise specified, this refers to percentages per volume.

To produce a washing composition according to the present inventionthere may e.g. initially be made two stem solutions comprising thecellulose derivative in the first solution (solution B) which is basic(pH 7-14, preferably 9) and may contain a small amount of the washingsolution (1-5%). The concentration of the cellulose derivative in theaqueous dispersion B lies preferably within the interval 0-10%, morepreferred 0-5%, e.g. 2% by weight. As an example of the cellulosederivative there may be mentioned "Bermocoll E (230-481)", whichrepresents different degrees of ethyl-hydroxyethyl cellulose, but alsoother types of cellulose derivatives will be obvious to the personskilled in the art after having read the present disclosure.

Solution A is added to solution/dispersion B as an alkaline aqueoussolution with a pH within the interval 7-14, e.g. 9. This solution maybe merely an aqueous alkaline solution with a pH within the aboveindicated interval, but it is preferred to use a neutral to alkalinewashing solution on account of the above mentioned preferred content ofsurfactants. The use of a suitable washing composition will be obviousto a person skilled in the art since this may only be of a type beingconventionally suited for the relevant type of washing. As an example itmay be mentioned that for the washing of vehicles there may be used astem solution such as "Forvask Vinter" (a liquid alkaline washing andcleaning composition containing White Spirit, complexing agents,surfactants, derivatives of glycol and water), "Micro" (a liquidtixotropic, alkaline washing and cleaning agent containing High FlashWhite Spirit, ethylenediamine tetraacetic acid natrium salt, surfactantsand water), "Maskin Shampoo" (a liquid alkaline washing compositioncontaining surfactants, ethyldiglycol, complexing agents, silicates andwater), "Super Cleaner" (a liquid alkaline washing compositioncontaining surfactants, complexing agents, silicates and water), allbeing obtainable from Thor Marcus Kjemiske A/S. These washingcompositions are of a liquid type, but also solid water-soluble washingagents may of course also be used.

The solution A and the solution B will be separately supplied as aqueousstem concentrates and are mixed in the system as mentioned supra intothe preferred end solution by adding the water. Thus stem concentrate Bmay be present in a mixture ratio between water and the cellulosederivative within the interval 1:5 to 1:100, e.g. 1:50, most preferred1:20.

Stem concentrate A may be adjusted according to the circumstances basedon the knowledge of the person skilled in the art, since the compositionor the use thereof will not differ from the conventional use when addingsolution B, but the effect of the combined washing composition will, onaccount of the above mentioned synergistic washing effect, besignificantly improved. Stem concentrate A may, all the same, when usingthe above mentioned stem concentrate "Forvask Vinter" I have a mixtureratio between the stem concentrate and water of 1:10-1:100, e.g. 1:50,but may in extreme cases also be used undiluted.

By using this two-component system no mechanical touch is needed beforerinsing/hosing as described.

As an example stem concentrate B (2) (20% aqueous solution) and stemconcentrate A (1) (50% aqueous solution, pH=9,0) are made separately.These two concentrates are ejected through individual pipes/hoses/lines(a,b) in quantities of 750 ml/min for concentrate A and 250 ml/min forconcentrate B, respectively, and are combined by joining thepipes/hoses/lines into a common line (4), preferably by using awater-based ejector system wherein the individual pipes (a,b) arecombined upstream of a narrowing of a water-leading ejector pipe (c),and are sucked up by an ejector effect into the water-leading pipe intothe feeding tank (5). The quantity of water flowing in the water-leadingpipe (c) may in this example be 5.7 l/min. It will be possible toregulate the mixing conditions being specified supra by using adjustablenozzles/valves on each separate pipe, and the mixing may be stopped byusing a stop valve 10 on the ejector pipe (c). From here it is possibleto spray the combined solutions directly onto the surface which is to becleaned, but it is preferred to let the combined solution made ready foruse, pass to a feeding tank (3). The feeding tank (3) holds just enoughsolution for a few washing operations. From the feeding tank (3) thesolution made ready for use may be sucked via a pump (5), preferably athigh pressure, to an air-adding foam-forming apparatus (6) such as afoam generator, and is sprayed onto the vehicle or the surface (8) whichis to be cleaned. The solution according to the invention will therebyform a layer of foam (9) on the vehicle, which after a short while(0.5-5 min) will agglomerate, surround, incorporate and "lift" the dustand dirt particles on the surf ace up and into the foam. Additionallythe cellulose derivative in this system will run together to form agel-like substance which, when hosed off, will draw and pull and removedust and dirt particles from the surface which is to be cleaned.

When considering very dirty conditions, the solution may be made furthereffective by incorporating or using a small mount of non-abrasive fiberparticles. The fiber material may be dispersed in the water (D, see FIG.2) or e.g. in the cellulose derivative and/or the alkaline washingsolution mentioned supra in a container and be pumped into the foammixture or the foam-forming preparation 6 by a pump 11 being operatedwhen needed or directly into the rinse-water. By-pass from the pump or amixing device keeps the mixture in dispersion. The added fiber materialwill adsorb the minuscule particles having a strong affinity to thesurface, and lead these into the gel-like mass from the foam. Then thesurf ace may be easily hosed clean, preferably by using a water jetmixed with fibers at high pressure. The solution in the container D mayin many cases substitute for the injection from container B.

An alternative, and preferred way to use the fiber dispersion is,however, to spray a dispersion of the fibers separately onto the surfacewhich is to be cleaned, after adding the foam. The foam compositionaccording to the present invention should be allowed a dwell time on thesurface, e.g. 0.5-5 min, before rinsing with water in which fiberpreferably is injected, and this procedure will further enhance thecleaning effect of the foam cleaning solution. The fibers arenon-abrasive and will have the effect of a soft paper tissue optionallythe fiber solution/dispersion may be made by using a detergent in thedispersing liquid for further enhancing the cleaning effect.

For the improved washing system and procedure according to the presentinvention, there may be used ground or unground fibers, and such fibersmay e.g. be obtained by conventional fiber processes producing anoptimal freeness. Thus the pulp material being used may e.g. be sulphitepulp, sulphate pulp, thermomechanical pulp, ground wood, semichemicalpulp, etc. Examples &such pulp material which may be used in the presentinvention may be leaf wood sulphate pulp (e.g. "Tofte EUC (ECF)") orneedle wood sulphate pulp (e.g. "Tofte 90 (ECF)"). An exemplary andpreferred pulp type may be "Folla CTMP 100/60" mechanical wood pulp, butcorresponding wood pulp types may also be used, as mentioned supra.

The length of the fiber particles may be varied within wide limits. Theymay have a conventional fiber length and may e.g. lie within theinterval 0.5 mm-5.0 mm. Very minor amounts &added fiber material in therinsing composition according to the present invention is necessary toachieve the wanted effect, but the volume of added fiber is notcritical, so that larger quantities may also be tolerated and evenpreferred. The concentration of the fibers in the fiber stem solutionmay be e.g. 0-40 g/l, preferably 5 g/l, although this is not critical.The weight of fiber may e.g. be 10 g fiber in a liquid volume of about2-10 1, also being a volume which may be used for washing a conventionalprivate car. It may also be used larger amounts of fibers than the onespecified supra, an then the effect is somewhat improved, but thequantity of fiber added in the process must not be so large that itcauses blockage of pumps and nozzles. If the nozzles leading the washingsolution according to the invention are flushed shortly after the fibersolution/dispersion has passed, it will be avoided that the system isblocked.

The fiber particles may easily be filtered in the sewer system togetherwith the adsorbed dirt and thus contribute to a cleaner waste water. Thesystem will in an oil separator function as an oil adsorbing agent, andthis will facilitate recirculation of the water.

The total effect of the above indicated sequence of events is that whenthe foam being produced according to the invention is rinsed off fromthe surface after a dwell time, the surface will be free from dust anddirt particles without the need for mechanical touch of the surface.

The aqueous fiber-containing rinsing stem-solution (D) is produced bydispersing/mixing the fiber material with water together withsurfactants to facilitate the dispersion process of the fibers.

The fiber material may also be used separately or in combination withconventional washing solutions for obtaining an improved washing result.

I claim:
 1. A process for washing a surface of a vehiclecomprising:providing an alkaline solution of a washing compositionhaving a pH in the range from about 7 to about 14; providing an aqueoussolution of a cellulose derivative; adding a fiber material to at leastone of said alkaline solution of said washing composition or saidaqueous solution of said cellulose derivative; combining said alkalinesolution of said washing composition with said aqueous solution of saidcellulose derivative, at least one of which contains the fiber material,to form a combined solution containing said fiber material; and sprayingsaid combined solution containing said fiber material onto the surfaceof the vehicle.
 2. A process for washing a surface of a vehiclecomprising:providing an alkaline solution of an alkaline washingcomposition having a pH in the range from about 7 to about 14; providingan aqueous solution of a cellulose derivative; combining said alkalinesolution of said washing composition with said aqueous solution of saidcellulose derivative to form a combined solution; adding a fibermaterial to said combined solution; and spraying said combined solutioncontaining said fiber material onto the surface of the vehicle.
 3. Aprocess for washing a surface of a vehicle comprising:disposing a fibermaterial onto the surface of the vehicle; providing an alkaline solutionof a washing composition having a pH in the range from about 7 to about14; providing an aqueous solution of a cellulose derivative; combiningsaid alkaline solution of said washing composition with said aqueoussolution of said cellulose derivative to form a combined solution; andspraying said combined solution onto the surface of the vehicle havingthe fiber material disposed thereon.
 4. The process according to one ofclaims 1, 2, or 3, wherein said step of combining the alkaline solutionof the washing composition with the aqueous solution of the cellulosederivative includes the aqueous solution of the cellulose derivativebeing combined with the alkaline solution of the washing compositionwith a concentration of the aqueous solution of the cellulose derivativebeing up to 5% by weight.
 5. The process according to one of claims 1,2, or 3, wherein said step of combining the alkaline solution of thewashing composition with the aqueous solution of the cellulosederivative includes the aqueous solution of the cellulose derivative andthe alkaline solution of the washing composition being combined in aration of about 1:3.
 6. The process according to one of claims 1, 2, or3, wherein said step of combining the alkaline solution of the washingcomposition with the aqueous solution of the cellulose derivativeincludes the alkaline solution of the washing composition being added tothe aqueous solution of the cellulose derivative by using a waterinjector and the alkaline solution of the washing composition beingpresent in a mixing ratio with water of from about 1:10 to about 1:100.7. The process according to one of claims 1, 2, or 3, wherein said stepof combining the alkaline solution of the washing composition with theaqueous solution of the cellulose derivative including passing thecombined solution through a foam producing generator.
 8. The processaccording to one of claims 1 or 2, wherein said step of adding the fibermaterial includes the fiber material having a fiber length of from about0.5 mm to about 5.0 mm.
 9. The process according to one of claims 1 or2, wherein said step of adding the fiber material includes adding thefiber material such that the fiber material is present within thecombined solution in a final concentration of up to about 40 g/l. 10.The process according to claim 3, wherein said step of disposing thefiber material onto the surface of the vehicle includes the fibermaterial having a fiber length from about 0.5 mm to about 5.0 mm. 11.The process according to claim 3, wherein said step of disposing thefiber material onto the surface of the vehicle includes disposing thefiber material onto the surface of the vehicle in an aqueous solutionhaving a dispersion of the fiber material in a concentration of up toabout 40 g/l.
 12. A precess for washing a surface of a vehiclecomprising:providing an alkaline solution of a washing compositionhaving a pH in the range from about 7 to about 14; combining saidalkaline solution of said washing composition with said aqueous solutionof said cellulose derivative to form a combined solution; spraying saidcombined solution onto the surface of the vehicle; and rinsing thesurface of the vehicle with a rinse solution containing a fibermaterial.
 13. The process according to one of claims 1, 2, 3, or 12wherein said step of spraying the combined solution includes sprayingthe combined solution at a pressure of about 1-150 bar.
 14. The processaccording to one of claims 1, 2, 3, or 12, wherein said step ofcombining the alkaline solution of washing composition with the aqueoussolution of the cellulose derivative includes obtaining a mixture ratiobetween the the aqueous solution of the cellulose derivative and thealkaline solution of the washing composition from about 1:1 to about1:5.
 15. The process according to claim 12, wherein said step of rinsingincludes the rinse solution being an aqueous solution having adispersion of the fiber material at a concentration of up to about 40g/l.
 16. The process to claim 15, wherein said step of rinsing includesthe rinsing solution having at least one surfactant.
 17. The process toclaim 12, wherein said step of rinsing includes the fiber material ofthe rinse solution having a fiber length of from about 0.5 mm to about5.0 mm.